Vacuum arc extinguishing change-over selector

Abstract

Disclosed is a change-over selector with a vacuum arc extinguishing circuit, including a central shaft, a moving contact driven by the central shaft to rotate, and a first static contact and a second static contact circularly arranged on insulation laths of a cage body of the change-over selector, where the moving contact is driven by the central shaft to rotate to switch between the first static contact and the second static contact, the moving contact and the first and second static contacts form a change-over selection main-circuit, a vacuum arc extinguishing sub-circuit including a vacuum tube is connected in parallel to the change-over selection main-circuit, the vacuum tube is opened after the moving contact is separated from the first static contact, and the vacuum tube is closed before the moving contact is electrically connected to the second static contact.

What is claimed is: 
     
       1. A change-over selector with a vacuum arc extinguishing circuit, comprising:
 a central shaft; 
 a first static contact and a second static contact circularly arranged on insulation laths of a cage body of the change-over selector; 
 a cam circularly arranged on the insulation laths and divided into a first conductive segment, a second conductive segment and an insulation segment which is located between the first conductive segment and the second conductive segment; 
 a moving contact driven by the central shaft to rotate to switch between the first static contact and the second static contact, the moving contact, the first static contact and the second static contact collectively forming a change-over selection main circuit; and 
 a vacuum arc extinguishing sub-circuit connected to the central shaft and in parallel to the change-over selection main circuit, the vacuum arc extinguishing sub-circuit including a vacuum tube and a roller which is fixed at an end of the vacuum tube and causes the vacuum arc extinguishing sub-circuit to move smoothly along a path on the cam amongst the first conductive segment, the second conductive segment and the insulation segment, 
 wherein the vacuum tube is opened after the moving contact is separated from the first static contact, and the vacuum tube is closed before the moving contact is electrically connected to the second static contact. 
 
     
     
       2. The change-over selector with a vacuum arc extinguishing circuit according to  claim 1 , wherein the vacuum arc extinguishing circuit is driven by the central shaft to rotate in synchronization with the moving contact. 
     
     
       3. A change-over selector with a vacuum arc extinguishing circuit, comprising:
 a central shaft; 
 a moving contact driven by the central shaft to rotate; and 
 a first static contact and a second static contact circularly arranged on insulation laths of a cage body of the change-over selector, 
 wherein the moving contact is driven by the central shaft to rotate to switch between the first static contact and the second static contact, the moving contact and the first and second static contacts form a change-over selection main-circuit, a vacuum arc extinguishing sub-circuit comprising a vacuum tube IS connected in parallel to the change-over selection main-circuit, the vacuum tube is opened after the moving contact is separated from the first static contact, and the vacuum tube is closed before the moving contact is electrically connected to the second static contact, and 
 wherein the vacuum arc extinguishing sub-circuit further comprises a vacuum tube drive mechanism, a support component for mounting the vacuum tube and the vacuum tube drive mechanism, a cam mounted on the insulation laths of the cage body of the change-over selector, the support component is made of an insulation material and is mounted on the central shaft, the vacuum tube drive mechanism is made of a conductive material and, together with the vacuum tube, is mounted on the support component, the vacuum tube drive mechanism has a force-bearing end in contact with the cam and a drive end in contact with a moving contact end of the vacuum tube, the cam is divided into three segments, a middle segment is an insulation segment, two ends are a first conductive segment and a second conductive segment respectively, the first conductive segment is electrically connected to the first static contact, and the second conductive segment is electrically connected to the second static contact. 
 
     
     
       4. The change-over selector with a vacuum arc extinguishing circuit according to  claim 3 , wherein the vacuum tube drive mechanism comprises a lever base fixed on the support component, a force-bearing bar disposed on the lever base in a slidable manner, a drive bar, and a lever hinged to the lever base, a roller in contact with the cam is mounted at an outer end of the force-bearing bar, an inner end of the force-bearing bar is hinged to one end of the lever, an outer end of the drive bar is hinged to the other end of the lever, and an inner end of the drive bar is in contact with the moving contact end of the vacuum tube. 
     
     
       5. The change-over selector with a vacuum arc extinguishing circuit according to  claim 3 , wherein the vacuum tube drive mechanism comprises a force-bearing bar disposed on the support component in a slidable manner, a spring base is disposed on a middle portion of the force-bearing bar, a roller in contact with the cam is mounted at an outer end of the force-bearing bar, an inner end of the force-bearing bar is sleeved with a spring and then is connected to the moving contact end of the vacuum tube, an outer end of the spring is in contact with the spring base, and an inner end of the spring is in contact with an end surface of a tube body of the vacuum tube. 
     
     
       6. The change-over selector with a vacuum arc extinguishing circuit according to  claim 2 , wherein the vacuum arc extinguishing sub-circuit further comprises a vacuum tube drive mechanism, a support component for mounting the vacuum tube and the vacuum tube drive mechanism, a cam mounted on the insulation laths of the cage body of the change-over selector, the support component is made of an insulation material and is mounted on the central shaft, the vacuum tube drive mechanism is made of a conductive material and, together with the vacuum tube, is mounted on the support component, the vacuum tube drive mechanism has a force-bearing end in contact with the cam and a drive end in contact with a moving contact end of the vacuum tube, the cam is divided into three segments, a middle segment is an insulation segment, two ends are a first conductive segment and a second conductive segment respectively, the first conductive segment is electrically connected to the first static contact, and the second conductive segment is electrically connected to the second static contact. 
     
     
       7. The change-over selector with a vacuum arc extinguishing circuit according to  claim 6 , wherein the vacuum tube drive mechanism comprises a lever base fixed on the support component, a force-bearing bar disposed on the lever base in a slidable manner, a drive bar, and a lever hinged to the lever base, a roller in contact with the cam is mounted at an outer end of the force-bearing bar, an inner end of the force-bearing bar is hinged to one end of the lever, an outer end of the drive bar is hinged to the other end of the lever, and an inner end of the drive bar is in contact with the moving contact end of the vacuum tube. 
     
     
       8. The change-over selector with a vacuum arc extinguishing circuit according to  claim 6 , wherein the vacuum tube drive mechanism comprises a force-bearing bar disposed on the support component in a slidable manner, a spring base is disposed on a middle portion of the force-bearing bar, a roller in contact with the cam is mounted at an outer end of the force-bearing bar, an inner end of the force-bearing bar is sleeved with a spring and then is connected to the moving contact end of the vacuum tube, an outer end of the spring is in contact with the spring base, and an inner end of the spring is in contact with an end surface of a tube body of the vacuum tube.